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Hilbert C*-modules and conditional expectations on crossed products

Published online by Cambridge University Press:  09 April 2009

Mahmood Khoshkam
Affiliation:
Department of Mathematics and Statistics University of Saskatchewan106 Wiggins Road Saskatoon, SK S7N 5E6Canada e-mail: [email protected]
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Abstract

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In this paper, we study the structure of certain conditional expectation on crossed product C*-algebra. In particular, we prove that the index of a conditional expectation E: B → A is finite if and only if the index of the induced expectation from B ⋊ G onto A ⋊ G is finite where G is a discrete group acting on B.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1996

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